5.4 Life Cycle Impact Assessment (LCIA)
| Aspect | G-27 (Buildings) / G-25 (Products) Choice of environmental indicators – screening and simplified LCA | |||||
Description |
The choice of a set of environmental indicators should always try to avoid pollution transfer. Currently, a large number of indicators can be found in the LCA literature. They fall into different: selected LCI indicators, midpoint life cycle impact assessment (LCIA) indicators, and endpoint LCIA indicators. Selected LCI flows can be useful in track some flow quantities: e.g. the use of secondary energy throughout the product’s life cycle. These are not impact indicators directly, but they can be useful in the interpretation phase of any LCA study. Mid-point LCIA indicators (or potential indicators) make it possible to characterize different environmental problems, such as climate change, ozone depletion, photochemical ozone formation, acidification, eutrophication and resource depletion. End-point LCIA indicators refer to actual damage categories such as damage to resources, damage to human health, and damage to the ecosystem.What are the useful and necessary environmental indicators and impact categories to be reported for an energy-efficient product or building? Which indicators and which methodology should be chosen? | |||||
|
related study objective |
☒ stand-alone LCA | ☒ comparative assertion | ||||
|
related study phase |
☐ | ☐ | ☒ | ☐ | ☐ | |
| goal and scope definition | inventory analysis (LCI) | impact assessment (LCIA) | interpretation | reporting | ||
|
relevant for |
 |
 |
 |
 |
 |
 |
| new buildings | existing buildings | building products | screening LCA | simplified LCA | complete LCA | |
Provisions |
In general, the set of indicators should be as comprehensive as possible, to avoid burden shifting. The EeBGuide does not provide predefined provisions regarding the number and the type of indicators for each study type, as they depend on the goal, the scope and the context of the study.Required environmental indicators to use are given in the EN 15978 and EN 15804 standards (which are harmonized indicators between the product and the building level), and also in the ILCD Handbook if other indicators need to be included.For screening and simplified LCA studies the choice of indicators is not regulated or limited. Generally speaking, in screening and simplified LCA a reduced set of indicators may be selected, which means that not all the EN 15804 and EN 15978 indicators have to be considered. In addition, optional indicators taken from the ILCD Handbook may be used to provide a more consistent set of indicators (if relevant). | |||||
Rules from: |
EN 15978 11 Calculation of the environmental indicators EN 15804 ILCD “[…] VI) MAY – LCIA methodologies: […] select complete set of single LCIA methods rather than selecting and combining individual LCIA methods” Provisions: 7.4.3.8 Reminder flows I) MAY – Use reminder flows to keep original information for specific purposes II) SHALL – exclude reminder flows from impact assessment III) SHALL – Clearly identify reminder flows in the flow name 8 Life Cycle Impact Assessment – calculating LCIA results Provisions: 8.2 Calculation of LCIA results ILCD Handbook – Part – Analysing of existing Environmental Impact Assessment methodologies for use in Life Cycle Assessment 4 Requirements for specific impact categories “For some impact categories, many alternative methods have been selected. This can be seen as a sign that there is no clear consensus on how to model such a method. Clear examples are acidification, eutrophication, land use and resources.” |
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Guidance |
The operational guidance for the environmental indicators can be broken down into two main aspects: the calculation rules for environmental indicators (in both CEN TC 350 standards and in the ILCD Handbook) and the number of indicators to select, depending on the study type.
1) Calculation rules (i.e. characterization factors and associated impact assessment method) for each LCIA indicator in EN 15804/EN 15978 A new method is now suggested for POCP calculations based on [Van Zelm 2008]. Other LCIA methods have been used so far for POCP calculations: for example the CML 2002 approach based on [Derwent 1998]. As a result, care has to be taken, and the method used for LCIA indicators should be clearly stated. In LCA studies across Europe, CML methods are frequently used for midpoint indicators. Also, EPD programmes usually provide results at indicator level, as is done by some generic databases. Using such data reduces the choice of impact methods and also yields a number of indicators to choose from. PS: Please note that the ADP guidance is given in a separate aspect. Harmonization of the LCIA indicators is expected soon. The aspect will be revised once there are agreed methods between CEN and ILCD. 2) Calculation rules for each indicator describing resource use and additional information (wastes etc.) in EN 15804/EN 15978 According to the ILCD Handbook, these flows are called ‘reminder flows’ (see ILCD rules above). The practitioner and LCA tool developer may be aware that, so far, not all the resource use indicators can be easily determined. In fact, the background databases used in LCA studies do not provide this information in a consistent way (e.g. ‘use of non-renewable primary energy excluding primary energy resources used by a raw material’). Others are potentially more easily available (e.g. ‘use of secondary fuels’). As the practitioner cannot influence the background data, this problem ultimately needs to be solved by the data providers. 3) Calculation rules for optional indicators (taken from the ILCD Handbook) Currently there is no agreement on a single calculation method for impact categories not covered in CEN TC 350 (but available in the ILCD Handbook), such as land use, toxicity or ecotoxicity. The type of LCIA modelling between midpoint indicators and endpoint indicators are is subject to discussion. Therefore the EeBGuide does not provide strict provisions on these aspects. Please consult the corresponding aspects for more detailed guidance on those aspects that are not mandatory in the EeBGuide. 4) Number of indicators to consider, depending on the study type. To select a relevant set of indicators, the practitioner should also try to have indicators covering the three area of protection: resources, ecosystems and human health. The indicators of EN 15804/EN 15978 correspond to these area of protection, but do not include all the impact categories, as some are still being debated within the LCA community. Additional aspects (see ‘Biodiversity’, ‘Land use’, ‘Toxicity and ecotoxicity’ etc.) provide guidance for the practitioner who would like to use them. For screening and simplified LCA it may be possible to conduct LCA studies using a single indicator under specific conditions. For example: – if the decision-maker is not very familiar with the LCA approach, or focuses only on energy or greenhouse gas issues; – if the full LCI data needed to calculate all the LCIA indicators are not available for some national context. However, it is strongly recommended that more than one environmental indicator be used, to avoid e.g. shifting of burdens. To that end, a selection of indicators from the EN 15978/EN 15804 standards (and from the ILCD Handbook if relevant) is recommended for screening and simplified LCA. The indicators considered in the SBA common metrics project may be considered for a screening or simplified LCA (if relevant for the goal and scope of the study): non-renewable primary energy, GWP, water consumption and waste. |
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| Aspect | G-28 (Buildings) / G-26 (Products) Choice of environmental indicators – Complete LCA | |||||
| Description |
The choice of a set of environmental indicators should always try to avoid pollution transfer. Currently, a large number of indicators can be found in the LCA literature. They refer to different types of indicator: selected LCI indicators, midpoint life cycle impact assessment (LCIA) indicators, and endpoint LCIA indicators. Selected LCI flows can be useful in tracking some quantity of flows, e.g. the use of secondary energy throughout the product’s life cycle. These are not impact indicators directly, but they can be useful for the interpretation phase of any LCA study. Midpoint LCIA indicators (or potential indicators) make it possible to characterize different environmental problems, such as climate change, ozone depletion, photochemical ozone formation, acidification, eutrophication and resource depletion. End-point LCIA indicators refer to actual damage categories, such as damage to resources, damage to human health, and damage to the ecosystem.What are the useful and necessary environmental indicators and impact categories to be reported for an energy-efficient product or building? Which indicators and which methodology should be chosen? | |||||
|
related study objective |
☒ stand-alone LCA | ☒ comparative assertion | ||||
|
related study phase |
☐ | ☐ | ☒ | ☐ | ☐ | |
| goal and scope definition | inventory analysis (LCI) | impact assessment (LCIA) | interpretation | reporting | ||
|
relevant for |
|
|
|
 |
 |
 |
| new buildings | existing buildings | building products | screening LCA | simplified LCA | complete LCA | |
| Provisions |
In general, the set of indicators should be as comprehensive as possible to avoid burden shifting. The EeBGuide does not provide predefined provisions regarding the number or type of indicators for each study type, as they depend on the goal, the scope and the context of the study.Environmental indicators to choose are given in the EN 15978 and EN 15804 standards (which are harmonized indicators between the product and the building level), and also in the ILCD Handbook, if other indicators need to be included.For complete LCA studies the environmental indicators mentioned in EN 15978 and EN 15804 should be used. However, optional indicators for impact categories not covered by the CEN standards may also be considered, if relevant for the LCA study. In this case, they may be taken from the existing LCIA methods in the ILCD Handbook | |||||
| Rules from: |
EN 15978 11 Calculation of the environmental indicatorsEN 15804 7.2.3 Parameters describing environmental impacts ILCD “[…] VI) MAY – LCIA methodologies: […] select complete set of single LCIA methods rather than selecting and combining individual LCIA methods” Provisions: 7.4.3.8 Reminder flows I) MAY – Use reminder flows to keep original information for specific purposes II) SHALL – exclude reminder flows from impact assessment III) SHALL – Clearly identify reminder flows in the flow name 8 Life Cycle Impact Assessment – calculating LCIA results Provisions: 8.2 Calculation of LCIA results ILCD Handbook – Part – Analysing of existing Environmental Impact Assessment methodologies for use in Life Cycle Assessment 4 Requirements for specific impact categories “For some impact categories, many alternative methods have been selected. This can be seen as a sign that there is no clear consensus on how to model such a method. Clear examples are acidification, eutrophication, land use and resources.” |
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| Guidance
|
The operational guidance for the environmental indicators can be split into two main aspects: the calculations rules for environmental indicators (in both the CEN TC 350 standards and in the ILCD Handbook) and the number of indicators to select, depending on the study type.
1) Calculation rules (i.e. characterization factors and associated method) for each LCIA indicator in EN 15804/EN 15978 Various LCIA methods are currently available to calculate the LCIA indicators mentioned in the CEN TC 350 standards. Recently, the ILCD Handbook has released the report ‘Characterization factors of the ILCD – Recommended Life Cycle Impact Assessment Methods’. In this report, several methods are analysed, and one is then suggested as the recommended method for each impact category. In the EeBGuide, the ILCD-recommended methods are provided for information in Appendix B for the following LCIA indicators: GWP, ODP, AP, EP, POCP and ADP (both elements and fossils). However, deviations in units are currently found between EN 15804/EN 15978 and the ILCD-recommended methods for:– AP (acidification potential, unit kg SO2-equiv. vs. accumulated exceedance, unit mole H+ eq); – EP (eutrophication potential, unit: kg PO43--equiv. vs. accumulated exceedance, unit: mole Neq). A new method is now suggested for the POCP calculations based on [Van Zelm 2008]. Other LCIA methods have been used so far for POCP calculations: for example, the CML 2002 approach based on [Derwent 1998]. As a result, care has to be taken, and the method used for LCIA indicators should be clearly stated. PS: Please note that the ADP guidance is given in a separate aspect. Harmonization of the LCIA indicators is expected soon. The aspect will be revised once there are agreed methods between CEN and ILCD. 2) Calculation rules for each indicator describing resources use and additional information (wastes etc.) in EN 15804/EN 15978 According to the ILCD Handbook, these flows are called ‘reminder flows’ (see ILCD rules above). The practitioner and LCA tool developer may be aware that, so far, not all the resource use indicators can be easily determined. In fact, the background databases used in LCA studies do not provide this information in a consistent way (e.g. ‘use of non-renewable primary energy excluding primary energy resources used by a raw material’). Others are potentially more easily available (e.g. ‘use of secondary fuels’). As the practitioner cannot influence the background data, this problem ultimately needs to be solved by the data providers. 3) Calculation rules for optional indicators (taken from the ILCD Handbook) Currently there is no agreement on a single calculation method for impact categories not covered in CEN TC 350 (but available in the ILCD Handbook), such as land use, toxicity or ecotoxicity. The type of LCIA modelling between midpoint indicators and endpoint indicators are is subject to discussion. Therefore the EeBGuide does not provide strict provisions on these aspects. Please consult the corresponding aspects for more detailed guidance on those aspects that are not mandatory in the EeBGuide. 4) Number of indicators to consider, depending on the study type. To select a relevant set of indicators, the practitioner should also try to have indicators covering the three area of protection: resources, ecosystems and human health. The indicators of EN 15804/EN 15978 correspond to these area of protection, but do not include all the impact categories, as some are still being debated within the LCA community. Additional aspects (see ‘Biodiversity’, ‘Land use’, ‘Toxicity and ecotoxicity’ etc.) provide guidance for the practitioner who would like to use them. For complete LCA studies, the full list of impact categories in EN 15978/EN 15804 should be used as well as missing categories taken from the ILCD Handbook if relevant for the goal of the study. |
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| Aspect | G-29 (Buildings) / G-27 (Products) Abiotic resources depletion indicator | |||||
| Description |
In LCA, different indicators can be used for assessing the use of resources. These can be based on a thermodynamic approach (use of energy or exergy indicators), on a mass flow approach (use of a total mass requirement indicator), on a surplus of energy that will be needed for future extractions (ecoindicator approach), or on a scarcity approach (use of the ADP indicator developed at CML Leiden). According to the ILCD Handbook, the CML method uses the abiotic depletion potential (ADP), given in kg of antimony equivalents, to be multiplied by the amount of a given resource extracted. For ADP, the annual production of the resource (the extraction rate) is divided by the reserves squared, and the result is divided by the same ratio for the reference resource, antimony [ILCD, 2011a]. The CEN TC 350 standards recommend using the ADP indicator, but different forms of APD can be used, depending on the type of reserve and the available extraction rates.Which indicator and assumptions should be applied in this guidance document? | |||||
|
related study objective |
☒ stand-alone LCA | ☒ comparative assertion | ||||
|
related study phase |
☐ | ☐ | ☒ | ☐ | ☐ | |
| goal and scope definition | inventory analysis (LCI) | impact assessment (LCIA) | interpretation | reporting | ||
|
relevant for |
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|
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| new buildings | existing buildings | building products | screening LCA | simplified LCA | complete LCA | |
| Provisions |
Adopt the provision of the indicators and methodology mentioned in EN 15978 and EN 15804 (‘Depletion of abiotic resources-elements’ and ‘Depletion of abiotic resources-fossil fuels’). EN 15804 refers to CML (Institute of Environmental Sciences Faculty of Science University of Leiden, Netherlands) as the characterization factor for ADP (elements and fossil), and the characterization factors for ADP fossil fuels are based on net calorific values at the point of extraction of the fossil fuels. | |||||
| Rules from: |
EN 15978: 12.5 List of indicators used for assessment and expression of results 11.1.2 Indicators describing environmental impacts EN 15804: 6.5 Impact assessment 7.2.3 Parameters describing environmental impactsILCD: 8 Life cycle impact assessment – calculating LCIA results Provisions: 8.2 Calculation of LCIA results ILCD Handbook – Part – Analysing of existing environmental impact assessment methodologies for use in life cycle assessment 4.11 Resource depletion “For some impact categories, many alternative methods have been selected. This can be seen as a sign that there is no clear consensus on how to model such a method. Clear examples are acidification, eutrophication, land use and resources.” ILCD Handbook: Recommendations for life cycle impact assessment in the European context 3.11. Resources depletion 3.11.7 Recommended default method for category 2 “The CML method is recommended in the ILCD framework since it captures scarcity by including extraction as well as reserves of a given resource. Characterization factors are given for metals, fossil fuels and, in the case of reserve base and economic reserves, mineral compounds [Oers 2002]. In addition, the method covers most of the substances/materials identified as critical by the European Commission’s Ad-hoc Working Group on defining critical raw materials (European Commission 2010).” [Oers 2002] give characterization factors for economic reserves, reserve base, and ultimate reserves. The characterization factors given for the reserve base are recommended, as this reflects a longer time horizon and the possibility of improvement in mining technology, making feasible the exploitation of previously sub-economic deposits. |
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| Guidance |
Practitioners should keep in mind that for the LCIA indicator ‘Abiotic depletion’ there is a methodology available that provides different assumptions regarding the estimate of reserves, i.e. ultimate, base or economic [Guinée 2001], [Oers 2002].So far, EN 15804 and EN 15978 do not specify which kinds of reserve should be considered for the ADP calculation. Over the past few years, most LCA or EPD data have reported the ADP (both fossil and elements) based on ultimate reserves according to [Guinée 2001]. Recently, the ILCD Handbook released the report ‘Recommendations for life cycle impact assessment in the European context’ (First edition, December 2010) [EC 2011]. In this guide, it recommended that the base reserve be used for the ADP calculation for all the elements (aluminium, copper, etc.). This guidance will be updated when EN 15804 and EN 15978 are revised.The ADP (fossil or elements) characterization factors based upon the CML 2002 method can be downloaded from: http://cml.leiden.edu/research/industrialecology/researchprojects/finished/new-dutch-lca-guide.html. In addition, another link provides the latest version of the characterization factors for the CML 2002 impact categories: http://cml.leiden.edu/software/data-cmlia.html.In the construction sector, such an indicator (ADP) may be adapted to take into account the local depletion of resources such as gravel. This is still a research topic but more information can be found in recent scientific papers, e.g. [Habert 2009] | |||||
| Aspect | G-30 (Buildings) / G-28 (Products) Land use indicator | |||||
| Description |
Land-use change is linked to human activities such as the exploitation of land for agricultural, industrial, residential, recreational, or other purposes. Currently, several LCIA methods exist, providing both midpoint and endpoint characterization factors. According to the ILCD Handbook, the midpoint characterization factor for land use, in the earliest stage of the cause–effect chain, is usually taken as the amount and quality deficit of land occupied or transformed. Some midpoint methods use indicators such as soil structure, soil pH or soil organic carbon. The endpoint characterization factor refers mostly to the quantity of species lost due to land use, or to the change in net primary production (NPP) of the land used [ILCD 2011a].Based on these different approaches, should a land-use indicator be included in the LCA of a product or a building? | |||||
|
related study objective |
☒ stand-alone LCA | ☒ comparative assertion | ||||
|
related study phase |
☐ | ☐ | ☒ | ☐ | ☐ | |
| goal and scope definition | inventory analysis (LCI) | impact assessment (LCIA) | interpretation | reporting | ||
|
relevant for |
|
|
|
|
|
|
| new buildings | existing buildings | building products | screening LCA | simplified LCA | complete LCA | |
| Provisions |
Land use should not be included as a mandatory indicator, as there is currently no agreed scientific method available (as also mentioned in the EN 15804 and EN 15978 standards). Yet, if the goal and scope of the study mention the use of an LCIA indicator for land use, then the indicator that is used for the assessment needs to be described and referenced. | |||||
| Rules from: |
EN 15978: 11. Calculation of the environmental indicators “Note: Indicators for which there is no scientifically agreed calculation method within the context of LCA e.g. human health, ecotoxicity, biodiversity, land use are not included” ILCD: 8 Life CYCLE IMPACT ASSESSMENT – calculating LCIA results Provisions: 8.2 Calculation of LCIA results 13 Annex B: Calculation of CO2 emissions from land transformation ILCD Handbook: Analysing of existing environmental impact assessment methodologies for use in life cycle assessment “For some impact categories, many alternative methods have been selected. This can be seen as a sign that there is no clear consensus on how to model such a method. Clear examples are acidification, eutrophication, land use and resources.” ILCD Handbook: Recommendations for life cycle impact assessment in the European context 3.10 Land use Existing methods for land use that can be used at the midpoint level include: [Baitz 2002] which was further developed by [Bos 2008], [Milà I Canals 2007], [De Schryver 2009] and [Beck 2010]. |
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| Guidance |
If land-use change is intended to be assessed, it is recommended that recent LCA literature be consulted to identify a feasible and appropriate indicator. Such literature may include:– the analysis of available existing LCIA methods for land use provided by the ILCD Handbook (report available online: http://lct.jrc.ec.europa.eu/pdf-directory/ILCD-Handbook-LCIA-Background-analysis-online-12March2010.pdf);– the results of the UNEP/SETAC working group on ‘Operational Characterization Factors for Land Use in Life Cycle Impact Assessment’ (LULCIA) [Beck 2010]– several publications in the International Journal of Life Cycle Assessment, such as a recent paper on the ‘Principles of inventory of land use on a global scale’ [Koellner 2012].This aspect will need to be revised when an approved method is available. | |||||
| Aspect | G-31 (Buildings) / G-29 (Products) Biodiversity indicator | |||||
| Description |
The loss of species and their diversity caused by destruction of their habitat has become one of the pivotal topics of environmental political actions in recent years. For years the scientific community has been working on completing a portfolio of considered environmental impacts, including taking biodiversity into account as a subject of protection.Which indicator and which methodology should be used? | |||||
|
related study objective |
☒ stand-alone LCA | ☒ comparative assertion | ||||
|
related study phase |
☐ | ☐ | ☒ | ☐ | ☐ | |
| goal and scope definition | inventory analysis (LCI) | impact assessment (LCIA) | interpretation | reporting | ||
|
relevant for |
|
|
|
 |
 |
|
| new buildings | existing buildings | building products | screening LCA | simplified LCA | complete LCA | |
| Provisions |
Adopt provision of the indicators mentioned in EN 15804 and EN 15978. The standards explicitly exclude biodiversity, because so far no scientifically agreed method is available. Yet, if the goal and scope of the study mention the use of an LCIA indicator for biodiversity, the indicator that is used for the assessment needs to be described. | |||||
| Rules from |
EN 15978: 11. Calculation of the environmental indicators“Note: Indicators for which there is no scientifically agreed calculation method within the context of LCA e.g. human health, ecotoxicity, biodiversity, land use are not included.” ILCD: 8 Life cycle impact assessment – calculating LCIA results Provisions: 8.2 Calculation of LCIA results ILCD Handbook: Recommendations for life cycle impact assessment in the European context 3.2.3 Measuring biodiversity loss Existing methods for biodiversity that can be used at the midpoint level include: [Baitz 2002], which was further developed by [Bos 2008], [Milà i Canals 2007], [De Schryver 2009] and [Beck 2010]. |
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| Guidance |
Currently discussions are ongoing about biodiversity indicators and methodology. So far there is no scientifically sound and commonly agreed method available. This aspect will to be revised if there are new outcomes from the discussions. | |||||
| Aspect | G-32 (Buildings) / G-30 (Products) Human toxicity and ecotoxicity indicators | |||||
| Description |
LCIA methodologies usually include midpoint or endpoint indicators for three area of protection: resources, human health and ecosystem. For the two last areas of protection, different indicators are currently available to assess the ecotoxicity and toxicity effects related to a product or a building life cycle. They classify the multimedia fate of chemicals into ecological compartments such as air, water and soil. On the one hand, accounting for toxicity and ecotoxicity effects allows a more comprehensive assessment in terms of the completeness of the set of indicators. On the other hand, these two impact categories are subject to very high uncertainties. Several indicators have been developed by the LCA community, which can lead to different conclusions [Van Caneghem 2010].Should toxicity and ecotoxicity indicators be used in an LCA of buildings? | |||||
|
related study objective |
☒ stand-alone LCA | ☒ comparative assertion | ||||
|
related study phase |
☐ | ☐ | ☒ | ☐ | ☐ | |
| goal and scope definition | inventory analysis (LCI) | impact assessment (LCIA) | interpretation | reporting | ||
|
relevant for |
|
|
|
|
|
|
| new buildings | existing buildings | building products | screening LCA | simplified LCA | complete LCA | |
| Provisions |
Adopt provision of the indicators mentioned in the EN 15804 and EN 15978 standards. These do not include toxicity or ecotoxicity methods, because there is so far no scientifically agreed method available.Yet, if the goal and scope of the study mention the use of an LCIA indicator for toxicity and ecotoxicity, the indicator that is used for the assessment needs to be described. | |||||
| Rules from: |
EN 15978: 11. Calculation of the environmental indicators“Note: Indicators for which there is no scientifically agreed calculation method within the context of LCA e.g. human health, ecotoxicity, biodiversity, land use are not included” ILCD: 3.3. Human toxicity ILCD states that “The use of USEtox as multimedia model, combining chemical fate and exposure with toxicological data, is recommended for midpoint indicators” for human toxicity. ILCD states that “For the endpoint characterization, it is proposed as an initial basis to apply the most recent values that are proposed by Huijbregts et al. (2005a) using disability adjusted life years (DALYs)” 3.3.5 Discussion on uncertainties and the importance of spatial-temporal differentiation 3.9 Ecotoxicity Existing methods for ecotoxicity aspects that can be used at the midpoint level include three groups according to their fate modelling: 1. Full multimedia fate modelling: USEtox [Rosenbaum 2008], ReCiPe [Huijbregts 2009], IMPACT2002+ [Jolliet 2003], TRACI [Bare 2003], 2. Partial fate modelling – Environmental key properties: EDIP 3. No fate modelling: Swiss Ecoscarcity [Frischknecht 2008] and MEEuP [Kemna 2005] ILCD states that “USEtox is preferred as the recommended default method for the midpoint evaluation of freshwater ecotoxicity impacts. This is equally consistent with the model recommended for toxicity impacts for humans. It results from a consensus building effort amongst related modellers and, hence, the underlying principles reflect common and agreed recommendations from these experts.” ILCD states that “No available method is recommended to address marine and terrestrial ecotoxicity.” Endpoint level for ecotoxicity includes: EPS2000 [Steen 1999], ReCiPe [Huijbregts 2009] and IMPACT 2002+ [Jolliet 2003]. 3.9.4 Discussion on uncertainties and the importance of spatial differentiation |
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| Guidance |
The LCA practitioner in the building sector should be aware of the existing and recommended LCIA methods for assessing toxicity and ecotoxicity aspects. Current uncertainties are substantial for these impact categories, although it is generally recognized that it is better to have one indicator than no indicator at all for an impact category.The LCA practitioner in the building sector should also be aware that current efforts are under way at the international level to harmonize the toxicity and ecotoxicity models: see e.g. the USE-oTox model.The latest developments in LCIA for human toxicity have included a new compartment ‘indoor air emissions’ in the USETox model (which is recommended for use by the ILCD). Accounting for indoor air emissions is increasingly relevant, as human beings spend most of their time inside buildings.Such new LCIA developments have to be connected to the EeBGuide aspect of Module B1 ‘Release of dangerous substances to air during the use stage’. The previous European project LoRe-LCA describes the basic concepts of such models in more detail (report available online). Practitioners should also keep in mind that national EPD programmes may also recommend using toxicity indicators that are not included in the core European PCR (EN 15804 and EN 15978). In this case, the practitioner should use them for national LCA studies (if relevant). This guidance will be précised and updated when the EN 15804/EN 15978 are revised. | |||||
| Aspect | G-33 (Buildings) / G-31 (Products) Ionizing radiation indicator | |||||
| Description |
‘Ionizing radiation’ is an impact category in LCA related to the damage to human health and ecosystems that is linked to the emissions of radionuclides throughout a product or building life cycle. In the building sector, they can be linked to the use of nuclear power in an electricity mix. LCIA methodologies (such as Eco-indicator99, IMPACT 2002+, ReCiPe) currently calculate the ionizing radiation effect of a product’s or a building’s life cycle.Should an ionizing radiation indicator be used in an LCA of buildings? | |||||
|
related study objective |
☒ stand-alone LCA | ☒ comparative assertion | ||||
|
related study phase |
☐ | ☐ | ☒ | ☐ | ☐ | |
| goal and scope definition | inventory analysis (LCI) | impact assessment (LCIA) | interpretation | reporting | ||
|
relevant for |
|
|
|
|
|
|
| new buildings | existing buildings | building products | screening LCA | simplified LCA | complete LCA | |
| Provisions |
Adopt provision of the indicators mentioned in EN 15804 and EN 15978 standards. They do not include an ionizing radiation indicator, because so far no scientifically agreed method is available. Yet, if the goal and scope of the study mention the use of an LCIA indicator for ionizing radiation, then the indicator that is used for the assessment needs to be described.As a proxy indicator, EN 15804 and EN 15978 provide a flow indicator for quantifying the radioactive waste (expressed in m3). This indicator should be used, particularly in a national context that relies heavily on nuclear energy, to avoid shifting of burdens (if only the GWP indicator is used). | |||||
| Rules from: |
EN 15978: 11. Calculation of the environmental indicators “Note: Indicators describing emission of ionizing radiation and their impact on human health and/or ecosystems in LCA level are intended for consideration during the revision of this European standard.” ILCD: |
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| Guidance |
This guidance will be updated when EN 15804 and EN 15978 are revised. | |||||
| Aspect | G-34 (Buildings) / G-32 (Products) Water consumption as a new impact category | |||||
| Description |
The water consumed during the life cycle of a product or a building can have an impact on the environment. This impact actually depends on the geographical location. For example, in some regions of the world, the same amount of consumed water may have different environmental impacts, depending on the available water resources. The current practice in LCA is that water flows are classified only according to their type (ocean, river, groundwater etc.). In this context, should a factor for regional availability be included? Should the scarcity of water be considered? What type of water (e.g. drinking water) should be considered? How should water demand be classified regarding its origin? | |||||
|
Related study objective |
☒ stand-alone LCA | ☒ comparative assertion | ||||
|
Related study phase |
☐ | ☐ | ☒ | ☐ | ☐ | |
| goal and scope definition | inventory analysis (LCI) | impact assessment (LCIA) | interpretation | reporting | ||
|
Relevant for |
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|
|
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| new buildings | existing buildings | building products | screening LCA | simplified LCA | complete LCA | |
| Provisions |
As there is no commonly agreed method for assessing the impact related to water consumption, scarcity of water is not considered at present. The provisions of EN 15804 and EN 15978 should be used, i.e. use of the indicator ‘net fresh water’. Yet, if the goal and scope of the study mention the use of an LCIA indicator for water consumption, the indicator that is used for the assessment needs to be described. | |||||
| Rules from: |
EN 15978: 11 Calculation of the environmental indicators EN 15804: 7.2.3 Parameters describing environmental impacts ILCD: |
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| Guidance |
1) Practical guidance for the use of EN 15804 indicator Two cases can be differentiated for guidance: practical calculation of the LCI indicator (currently provided in the CEN TC 350 standards) or available references for the use of a new impact category indicator for water consumption.– If the ‘net fresh water’ indicator is used according to EN 15804 and EN 978, it should be calculated as the difference between the water input and water output from a product system. Thus cooling and turbine-use inventory flows are not to be accounted for in the indicator. Salted water is also excluded, as this category deals only with ‘fresh’ water.
At the standardization level, the ISO is also working on a new standard on water footprint: ISO/CD 14046 Life cycle assessment – Water footprint – Requirements and guidelines. Revision of this aspect is required if a generally accepted method is available – and used by the EN 15804/15978 standards. Please also note that some of the EPD programmes consider the inclusion of water in one way or another. Additional information on methodologies can be found in such EPD programmes. However, the various data sources could refer to different methodologies for the calculation of a water indicator. |
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